i8i8 The Trees of Great Britain and Ireland Cultivation Though no English writer has as yet fully realised the economic importance of the black Italian poplar, and though consumers have hardly recognised the value of its timber for many purposes ; yet in France and Belgium it is more generally planted than any other tree, and, as I shall be able to show, will produce a quicker and larger return than any other, if properly grown and converted into timber. None of the poplars are particular as to soil, provided it is moist in summer; and though, like all other trees, they grow faster and larger on good than on bad soils, yet they succeed in cold wet and undrained valleys and meadows, and are resistant to frost at all seasons, and are little liable to fungoid and insect attacks. From an ornamental point of view the black Italian poplar is inferior to the grey and the white species, but its large red clusters of flowers appearing in spring on the bare branches are very beautiful, and its extremely rapid growth makes it suitable for situations where no other tree will attain a large size in a lifetime. Before planting poplars it is important to have a variety which has proved hardy and vigorous on a similar soil and situation; and though nothing seems likely to surpass P. robusta and P. Eugenei where the climate suits them, I shall not give up the propagation of the red-petioled P. serotina until the others have proved their ability to endure the worst vicissitudes of our climate. The green-petioled variety, though it seems equally vigorous and hardy in any soil, is not so erect, and seems to have more spreading branches. Owing to the general confusion between this tree and the true black poplar which has prevailed among English botanists and foresters, few of whom seem to have distinguished the two trees, I must point out that many of the statements ^ which have been made about the latter species really apply to the former. Grigor states ^ that on a sandy soil (probably in Morayshire) the black Italian poplar in a mixed plantation, twenty-four years planted, measured 60 ft by 3^ ft,, when larch was 48 ft, by 3 ft 4, in,, beech 40 ft by 2\ ft,, sycamore 34 ft, by 2 ft, i in,, and Scotch elm 33 ft by 3 ft Thirty trees planted by my father in a cold clay soil not worth 5s, per acre, in a situation remarkably subject to late and early frosts, in forty-eight years averaged 120 cubic feet and realised ^3 each ; and two trees planted by myself in a clay soil close to the stream at Colesborne attained in fifteen years 56 ft, by 5 ft, 3 in. and 50 ft. by 3 ft. 2 in. respectively. Fifteen trees felled recently in a more shaded position and closer together in the same valley were at eighty-five to ninety years old of considerably smaller girth, and had increased but little during the last thirty years, some of them being more or less decayed and hollow at the base. This lot, though much older, only averaged 70 cubic feet, and proved to me that a sunny situation and plenty of room are essential. In another part of the same valley where the land is ' In Trans. Surveyors' Institution, 1904, p. 226, my advocacy oi P. serotina as a valuable timber tree was erroneously printed under the heading Black Poplar, instead of Black Italian Poplar; and my remarks have been quoted by Nisbet and Sir Herbert Maxwell (in Green, Encyclopcedia of Agi-ic. iii. 308) as referring to P. nigra. Arboriculture, 326 (1868).